For Functional testing it is important to support a specific development environment, the ability to create reports about testing, automatic registration of detected defects, presence of recovery-scenarios. For load testing tools it is necessary to support a protocol that uses by application under test, the presence of built-in tools for monitoring of servers parameters, opportunity of flexible adjustment of the load testing scenarios, the availability of tools to analyze results and create reports on load testing.
The availability of documentation and technical support line has an important role in selecting of testing tools. You should pay attention to the existence of specialized forums dedicated to testing tools – the existence of a forum on a specific instrument and, more importantly, a large group of active users verify the prevalence of this tool, which further could help to quickly get an answer to your question.
You should be also guided by worth of testing tools – if you are planning a one-time testing, then buy an expensive tools is inappropriate. As an alternative to purchasing licenses for the tools of testing can be to rent a license (purchase temporary licenses), which is usually much cheaper.
We prefer to work with the testing tools of HP and IBM, although we have experience in using tools from other manufacturers and our own tools of automated testing. Before we start the developing of automated tests, we perform analysis and prepare a report based on which the customer decides what testing tool it more suitable for him, but often there are situations when the tool is selected in advance.
Almost every problem can be solved by any testing tool, but the complexity and cost of solutions would be very different. For example, if your test automation tool has no its own debugger of scripts, the development and debugging of scripts will increase time required for testing by 30-40%.
Lack of tools for analyzing of results and reporting about testing could lead to the loss of the advantages of automating of functional testing before manual testing – if the time needed to analyze the results of automated testing, comparable to the time required for manual testing, then talk about the benefit is not necessary any more.